Yesterday’s MODIS/Aqua satellite image shows a couple of small slicks in the Main Pass area, a region jam-packed with offshore oil and gas platforms and pipelines. The two slicks we’ve outlined in yellow below appear to be closely associated with two recent National Response Center oil spill reports, one (#980916) submitted on June 27 and the other (#981157) on June 29. The report on June 27 indicates the spill location (but not necessarily the source) as a manned oil/gas platform in Main Pass Block 299, installed in 1991 and operated by Freeport McMoRan Energy LLC. (LLC…really? Think about that for a moment. This is a division of a multinational mining and energy conglomerate that, among other things, operates the massive Grasberg Pit in West Papua that is steadily smothering lowland rainforest with tailings.) No amount spilled, or estimate of the size of the oil slick, is given in the report. The slick is described as being dark brown, which indicates something thicker and more substantial than the “unknown sheen from unknown source” so frequently described in NRC reports.

Detail from NASA MODIS/Aqua satellite image taken June 29, 2011. Red pushpins mark locations of NRC spill reports on June 27 and June 29. Pink dots mark active oil/gas platforms in Federal waters. Scattered clouds and shadows at lower left. Strong sunglint on this portion of the image makes areas of smooth water (including oil slicks) appear very bright.

The possible slick seen on the June 29 MODIS image in that area covers 75 km2. At 1 micron (one 1,000th of a millimeter) thick, that would be 19,800 gallons (a “medium” spill by Coast Guard definition). But standard guidelines for estimating a slick’s thickness from its appearance put a “dark brown” slick in the 50 micron range. That would be a spill of 990,000 gallons (23,571 barrels), and a Clean Water Act fine of 26 to 101 million dollars. But somebody in the federal government needs to step up and actually start fining companies for these spills (our intern Michelle is looking into this enforcement question). We think this is critical to improve offshore drilling safety: a credible and consistent financial incentive for operators — large and small — to take better care of business, one of the keys to avoiding the next major spill.

Possible oil slicks delineated with yellow line.

The June 29 report describes a 125-gallon spill in Main Pass Block 313 creating a “silvery sheen” (very thin slick) of oil about 26,000′ long x 2,600′ wide drifting southeast from the source. The report gives the spill location (again, not necessarily the source) as a platform operated by Chevron. This roughly matches what we observe on yesterday’s MODIS image: a possible slick that’s about 9 miles long and 25 km2 in size, beginning about 3-1/2 miles southeast of the platform location. Assuming the slick is 1 micron thick, the total amount of oil it contains should be closer to 6,600 gallons (157 barrels).

Detail from NASA MODIS/Terra satellite image taken June 28, 2011. Red pushpin marks location of former Taylor Energy platform. Tip of Mississippi Delta at upper left; scattered clouds and shadows at right. Strong sunglint on this portion of the image makes areas of smooth water appear very bright.

We’ve now collected dozens of satellite images and air photos showing a persistent oil slick at this site, including this image from June 19 showing a slick at least 17 miles long, and possibly more than 30 miles long (a small patch of clouds interferes with the view):

So what’s happening here to finally stop this chronic oil spill? One of our readers just noted that there is no evidence of vessel activity at the site now. According to the latest Diamond Offshore rig status report (dated June 14) the rig that’s been working to plug the leaking wells at this site – the Ocean Saratoga – is scheduled to be pulled off the site by mid-July and sent to a 5-year job elsewhere in the Gulf. If there isn’t any tracking data indicating vessel activity at the site, maybe they’ve already pulled out – without completing the job, based on the 10-mile-long slick we observed yesterday.

According to their rig status report, no other Diamond Offshore rig is assigned to the site. Maybe another drilling company is under contract to bring in a rig to continue the plugging operation.

This plugging operation is obviously a low-priority job. Possibly because, as far as we can tell at this point, no fines are being levied against the operator for the oil being continuously spilled into the Gulf at this site — so they have no financial incentive to pay higher rates to get the plugging job done quickly. Our summer intern Michelle is working to help us determine who to blame for setting up this moral hazard: the Coast Guard? BOEMRE? EPA? Department of Justice?

Following up on Ben’s post Tuesday – onshore oil and natural gas drilling can impact water in different ways:

1) Water withdrawals – drilling and hydraulic fracturing (fracking) require large quantities of water. The high-volume slickwater fracking performed on Marcellus Shale gas wells can use up to 3 million gallons of water per frack. It’s not unusual for a single well to be fracked several times; and for a single drilling location to host several wells reaching out in all directions. Water can be brought in by tanker truckor pipeline. The closer the water source, the cheaper it is for the operator, so often they request permission from state and local authorities to take water directly from nearby streams. As an example, XTO Energy (a division of Exxon) is seeking permission to withdraw up to 250,000 gallons per day from Oquaga Creek in upstate New York, a small trout stream annually stocked by the state. My father-in-law and his fly-fishing buddies know this stream personally and think this withdrawal would destroy it as a trout stream. Pennsylvania has already issued many water withdrawal permits for drilling and other activity (map).

2) Water disposal – the fluids used for drilling and fracking contain a wide variety of potential contaminants. Produced water — water originally held in the target geologic formation that is produced along with the gas — can contain elevated levels of dissolved salts and, in some cases, low level radioactivity. Spills of these fluids, and leaks in the plastic liners in fluid-reserve pits on the drillsite, can contaminate surface streams and near-surface groundwater. Standard municipal wastewater treatment facilities are not equipped to remove some of the contaminants in these fluids, so specialized treatment facilities must be built to process this wastewater before it can be released to streams and rivers.

3) Groundwater contamination – when it comes to drilling safety, the devil is in the most mundane of details. Cement, for example. Cement pumped into the bottom of the well, and sealing off the fracked intervals, is the main line of defense to prevent gas and fluids from moving where you don’t want them to go. Poor cementing was the proximal cause of the disastrous Montara blowout and spill off Australia in 2009, and the fatal BP / Deepwater Horizon blowout and spill in the Gulf of Mexico last year. A recent Wall Street Journal investigation revealed that problems with cementing are alarmingly common. Casing failures, corrosion, poor drilling practices and other factors can also allow unwanted fluid migration. The end result: a growing roster of cases where drilling activity is related to the contamination of drinking water supplies across the nation.

By the way, thanks to careless use of drilling terminology by some environmentalists and politicians, a big semantic argument has broken out, focused on whether the hydraulic fracturing procedure itself is the cause of contamination. More on this topic later, but we think this argument misses the mark: fracking is the repeated pumping of fluid into the well at extremely high pressures designed to break open rock, so any weakness or flaw in the well design or construction (like a poor cement job, for example, or cheap imported steel casing) is much more likely to lead to failure in a fracked well, than it would in one of Dad’s old-fashioned unfracked wells.

By The Way, Part Deux: National energy legislation in 2005 exempted the drilling industry from disclosing the chemicals they use in fracking, making it difficult for homeowners to monitor the quality of their drinking water without spending a fortune on water analysis. ShaleTest is a new outfit that is trying to help homeowners with this.

4) Stormwater runoff contamination of surface waters – this is the unglamorous way that streams, ponds, wetlands and rivers could be impacted by drilling activity. A drill site, after all, is essentially a concentrated construction zone several acres in size: trees and brush are cleared, the land is graded flat, gravel is trucked in and spread out to create a space for all the trucks, equipment, supplies and people needed to drill, frack and complete a well. Access roads are built; pipelines and other utilities are installed. All of these elements of drilling infrastructure are potential sources of muddy runoff when it rains, changing the physical and chemical properties of streams with impacts on the aquatic life and downstream water users. The construction industry in general is subject to Clean Water Act rules to control stormwater runoff, but – yes, you guessed it – the drilling industry is exempt from those rules.

Ben’s work is focused on investigating if this potential for runoff really is a measurable problem. If so, it could complicate the decades-long, multimillion dollar effort to restore water quality in the Chesapeake Bay. This excellent map, created by SkyTruth volunteer Dorn Moore of Greenspace GIS, shows that over one-third of the Bay’s watershed overlaps with the Marcellus Shale gas play.Assuming one drilling location per square mile, that could mean as many as 25,000 drilling sites will be built in the Bay watershed (even more as other geologic formations, like the Utica and Ithaca Shales, are targeted for drilling).

If these sites cause measurable degradation of water quality, that could be very bad news for the Bay.

Saratoga emerged from Chapter 11 a year later. We don’t know for sure if Saratoga owns the apparently leaking well, but it seems likely. This LLC shell-game with offshore drilling sure can be confusing — we call it Responsible Party Whack-a-Mole. And it sure does make us uneasy to learn about small, bankrupt companies responsible for operating and maintaining offshore oil and gas wells, when other livelihoods are put at risk from both chronic pollution and catastrophic spills.

We’re continuing to look for better imagery of the area, and the Gulf Monitoring Consortium will continue to coordinate our efforts to investigate and publish information about pollution incidents like this one.

SkyTruth and/or its third party tools use cookies to monitor traffic in the aggregate on our websites and applications and to improve user experience. If you continue browsing, we'll assume you agree to the use of cookies. You can change your cookie settings at any time in your browser settings. Find out more in our privacy policy.